If netconsole is built as a module, you can't use it to capture output before the module gets loaded. Rebuilding Fedora srpms (to get Fedora patches) takes pretty long, which makes testing slow.
I have something particular I am testing now (probably a nouveau related crash) that crashes for netconsole gets loaded (though I tried to add it to the initramfs to get it loaded fairly early). I am not sure if it will be early enough even if it is built in. I won't know until sometime tomorrow. But if it does get loaded early enough to handle video card related stuff, it seems like it be worth having built into debug kernels.